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grease_boy writes "A UK company will start selling server racks submerged in oil baths within a year. Very-PC is working on prototypes and says that because oil transfers heat more efficiently, power usage can be cut by fifty percent."

It was Curly, actually. In one Three Stooges short, Curly was covered in oil (from an oil well he just discovered, you pervs), and Moe said something like "Whatcha doin, knucklehead?" To which Curly says "You know what they say! The oily boid gets the woim! nyuk nyuk nyuk"

The Hot cha cha cha was Jimmy Durante, and I just added that in for kicks.

The funny part is that this post will get modded informative. If there are any other jokes that need in-depth explanations, I'd be happy to serve.

There really needs to be a "-1 Disgusting" mod for posts like yours. It made me laugh initially, but then I shuddered when the mental image hit. I'm going to try not to think about that for the rest of the day. Or any other day for that matter.

It's not a step forward. It's a step back in a sense. This has been how large transformers have been build for decades. I'm sure that this application will use the same oil as street transformers, and I've seen a number of hobby applications of this in machine cooling before.

Slashdot ran a story on total-immersion computing using an oil bath, oh, four or five years ago now. He was using mineral oil. This is not to say it's a bad idea - on the contrary, it's rather overdue on the technology front. However, it does take about this amount of time to go from hobbyist to early market, so maybe this story should have been expected some time this year or next.

Oil IS an accepted dielectric fluid! Highly refined mineral oils are widely used for cooling and insulating electrical equipment (like the transformer that feeds power to your house), and relatively cheap, even given current petroleum prices.Specialty fluids like Fluorinert are less messy when you need to work on the submerged parts, but that stuff is EXPENSIVE. How about over $300 per LITER?

Exactly, the website and business proposal seem very amateurish. They actually tried using motor oil before realising that by some strange, arcane and entirely unpredictable process it correded PCBs? Am I being too presumptive in assuming that these people know very, very little about electronics?

Why on earth they didn't at least think to use highly-refined mineral oil like transformer oil is beyond me. I mean, filling a server with motor oil? Are you kidding me?

Someone saw the Tom's Hardware cooking-oil-cooled-PC experiment that was published a while back, and saw an opportunity to make some money. They didn't realise that Tom's Hardware used oil because it was headline-grabbing, cheap, easy to purchase and --oh yeah-- wasn't being used to cool a server that had to be stable and reliable. That doesn't mean it's the best choice of coolant.

Hell, you could do it with purified water if you wanted to, but your uptimes might take a hit.

Common sense dictates that submerging your high-end PC in cooking oil is not a good idea. But, of course, engineering feats and science breakthroughs were made possible by those who dared to explore the realms of the non-conventional. Members of the Munich-based THG lab are only too happy to confirm this fact. And not only did we find that our AMD Athlon FX-55 and GeForce 6800 Ultra equipped system didn't short o

That statement, together with VeryPC's own statement that they did intial prototyping with normal oil but realized it could corode the systems makes me somewhat... "doubtful" as to their ability to create stable servers.

Fluorinert [wikipedia.org], which is what is used for supercomputers, costs something like $3000 a gallon. Perhaps Garimella should consider the implications of that for a company wanting promoting immersion cooling for ordinary servers.

Every other fluid in this class has the same set of issues, unfortunately.

They may be "clean" and non-toxic, but they're decidedly NOT environment friendly compared to oils-and they're a hell of a lot more expensive than oils and not as effective at cooling things.

The reason why the fluids are used in the supercomputer industry is more the mess caused by the oilson everything- and they're actively cooling the systems. Oils are actually superior to the fluidsin heat-transfer terms- it's why you have oil filled transformers for power distribution instead ofdielectric fluid filled ones. The specific heat of Novec is actually less than air's- the only advantagesthese fluids have is that you can effectively move a LOT more of it quickly over a surfaces being cooledwithout noise and you can refrigerate the stuff to below ambient to temperatures close to the freezingpoint of water without condensation risks.

Oils tend to have issues with active cooling. Unless you're implementing vapor-phase, stirling cycle,or aggressive peltier active cooling below ambient, you are actually better off with oils than the fluidsas they won't work as well at cooling- you'll be better off with air cooling.

This has been discovered by the overclock crowd and they have done a handful of oil-immersed PC's.The main reason why you don't see a lot more of those oil immersed PC's is oil wickingby the wires. Each point where a connector would be or a peripheral like a CD/DVD or hard disk ishooked in has wires coming out of the system that will wick the oil or dielectric fluid out all overthe place. In order to deal with this specific problem, you'd have to resort to specialized sealedheader and other connectors for each edge case for SATA/PATA, VGA/DVI, etc. Those don't come cheap,so the overclocker crowd tends to just resort to fishtank and similar plays for lan parties orPAX/QuakeCon, etc.

So, in the end, it is a mixed bag. The oils are messier, but are actually more environmentally friendlythan the dielectric fluids- and they have a higher heat capacity and thermal conductivity in many cases.

I can see how people would want to do this when hacking their own motherboard, but I would not like to see this become commonplace. For a starter, what to do with the oil after it has been used. I presume that you cannot reuse the oil to bake fries in. And I would really like to know if this would have negative implications considering the life-time of the equipment as well.

THat oil can be reused real easy. e.g. to convert it to diesel oil to run your car on.

The only problem i can see is that once you bath your pc components in oil you cannot reuse them elsewhere because the contacts get all dirty. Also i wonder if the components on a Motherboard can handle being oaked in oil. I can imaginge some component will solute in oil after a month or so.

Note also that Harddrives can not be soaked in oil (they need the air cushing )

There are many wonderful highly toxic chemicals that can easily clean the oil off...But back to the main concern... Obviously when needed you would drain the oil and filter it so it can be reused for cooling again. I would assume that the system would be closed and the same oil could be used for dozens / hundreds of years.

I would also assume that servers could be more dense - much more dense than traditional blade servers as long as you pump the oil around a little. The spacing between boards could be drast

Actually, vegatable oils (natural ester fluids) have been used as an alternative dielectric fluid for several years now. A fair number of distribution-size transformers are filled with it, as it has less environmental consequence in the event of spills. It does have lower oxidation stability than mineral oil, so the system would have to be sealed.

Yell at me if you like, but I live in a small apartment, use compact florescent bulbs where practical, and don't have a car. And yet I still use more resources than a starving peasant, so I guess we all "could do better". You can buy into this "offsets" garbage if you like, but it is just as much B.S. as the conservatives disregarding everything the man has to say just because he happens to be a hypocrite. He may not be adding CO2, but he is certainly using up resources at a prodigious rate. He plays up thi

You are right. It IS marketing propaganda. If you have 1.3MW of power used by CPU/motherboard/drives, you still have to remove 1.3MW if heat. Period. Using oil just lets you MOVE the heat easier (and quiter, and in less space), but that heat still has to go SOMEWHERE.Of course, depending on the location, it might be easy enough to circulate the oil to cooling coils outside, but that still takes energy.

Given these guys obvious engineering expertise (not), I wonder if they have ever heard of Polyalphaolef

It's probably not far off. Bear in mind that a lot of the 300W of your power supplies in each system is dissipated as heat. I've got a datacenter that's had water cooled racks installed (which as you might imagine, has horrific 'overheads' on installation, cableing and maintenance). At £5k/rack, + overheads, it was still a cheaper solution than standard 19" rack + aircon bill.

Well, the fuzzy thing about this is that the heat still has to go somewhere. Granted you may not be powering thousands of tiny, whiny fans to remove the heat from the device, but now you've got a heated mass of oil that itself needs to be cooled off.

They could take a lesson from the much-maligned President Bush, and use deep groundwater (I believe he has pipes going down 300 ft at his Crawford, Texas home) to provide a heat sink. Alternately, copy Toronto, where a large pipe is being constructed in Lake Ontario that provides water at approximately 4 degree C to cool office buildings in the downtown core.

My question is "Why do they have to bathe the components in the liquid?". I seem to recall old stereo components with finned heat sinks sticking ou

"Couldn't some variant of this technology be used, where the actual PCB's don't get near the liquid, but the heat sinks are immersed in it?"I've got this great idea! Let's put the liquid in TUBES and have pumps to circulate the liquid.

The answer is simple: That's already being done. This is only news because it sounds crazy and someone did it. It sounds crazy on the surface because 'everyone knows' that liquids and electronics don't mix. You've got to have a bit of knowledge about physics to overcome t

Do data centers really use as much power cooling the server farms as running them?

More or less, yes. Efficiency on the A/C units is usually around 2:1 and sometimes approaches 3:1, that is you get twice the cooling as the energy you put in. Since nearly 100% of the power in to servers is expressed as heat, you need the same amount of cooling. Now add inefficiencies in the cooling architecture, power for fans in the servers, inefficiency of semiconductors when running hot, etc. When you add it all up you're approaching 50% of the total power consumption.

Its a disingenuous marketing claim though. Cooling oil is no more efficient than cooling air and convection won't be the final word at an industrial scale - they'll need pumps which consume as much energy as fans

On the plus side 10kva in a oil-cooled rack will be a hell of a lot quieter than 10kva in an air-cooled rack with a hundred 3cm fans running at 7krpm.

I wouldn't go so far as to call it disingenuous.You got it all right regarding A/C inefficiency.So right there the efficiency improvement means that C/kva ratio is better. (More cooling for less power)

But the goal of using oils is their heat transfer properties. Allowing for low speed pumps and radiators. In an ideal system, it would have integration into the building. Servers in their oil, heat exchanged with some central system that leads to roof radiators.

A heat pump (pumping hot air out and pumping cold air in) is not an air-conditioning. That's called a fan (albeit very large) and yes, they can move a lot of energy using minimal energy to do so. That's just displacements of air and doesn't work if the exterior temperature is higher than the required internal temperature.Generating the cold air (by extremely cooling the hot air) as a real air conditioning does is not that efficient. You can't possibly remove more energy out of a system than the energy you p

A heat pump (pumping hot air out and pumping cold air in) is not an air-conditioning.

A heat pump is a generic term for a system that uses compression and expansion of refrigerant to transfer heat. It can either be run as an A/C to cool a space and dump heat to the outside, or as a heater to heat a space by taking heat from a ground loop.

What you're talking about is a simple ventilation blower, not a heat pump.

HWSpirit did a proof of concept here [hwspirit.com]. I wonder if these guys were inspired by that.

But it's a decent idea. Oil has a high thermal capacity and will circulate through convection keeping the temperature down. Repairs and upgrades aren't going to be all that pleasant but some swarfega will get the grease of your hands after changing the motherboard.

They will have to run the HDDs outside the oil because they do, in fact, need ventilation. Though perhaps you can get totally sealed HDDs from somewhere by now.

However, the main problem I see is connectors. Existing connectors have been developed to work in air, except for a few exotic types. Watertight connectors are designed to work with wet environment outside and dry electronics inside, not vice versa, but in any case existing technology would require standard connectors to be used entirely submerged in dielectric. Modern connectors have much smaller contact surfaces than they did even ten years ago, and the distance liquid would have to move by capillary action before breaking the contact is quite small. It's hard to see how you could do accelerated life testing for such a system, which means it could be many years before we know whether they are reliable or not.

I recall when doing research involving electronics in Fluorinert we had to make soldered connections in liquid. Contacts that were frequently made and broken could be pressure contacts, but that is quite different from the situation in a server. And if we had known of a cheap substitute for Fluorinert we would have used it. The majority of oils degrade quite interestingly - you wouldn't expect bacteria to live in them but they can and do if the conditions are right.

These guys may have a workable solution to all the problems, but I can't help thinking that technology will make the concept obsolete. How does the performance of an old Fluorinert-cooled Cray stack up against a modern server in flops and GBit/s of IO per watt? (Hint: Don't bet on the Cray.)

One other problem that folks have had in the past with running computer components in oil is that the stuff tends to creep through cabling and leak out the distal end of the cable. Messy. That means that networking, keyboards, monitors, hard drives, etc will very likely have to be coupled to the motherboards by some wireless technology. Not a problem in a home, but is there going to be an interference and bandwidth issue with hundreds or thousands of wireless devices in a server farm?

I wonder if these servers would have to be "disposable" Trying to swap out parts is going to be a major problem. Think of the time to drain the server and get it clean enough to swap out a part. Forget about adding RAM. Probably not an issue for places that use many 1Us for a web front end but for a lot of places it seems like a big pain. I hate to bring it up but what about the fire hazard. Most oils I have see will burn if you get it hot enough.For everyone that was posting about hard drives I doubt tha

The design with the Cray 2 was a bit excessive. They just had the heat reach fluorinert's boiling point and there was a vapor collector and a condensor tower [flickr.com]. As you'll recall, the temperature of a liquid will not never exceed the boiling point until it all turned to vapor. That's why car are water cooled. If you have insufficient heat transfer from the radiator, the vapor pressure blows the cap and you have a really visual feedback that it's time to stop. You won't damage anything if you stop before you evaporate all your coolant. Fluorinert boiled at 56 C, a convenient temperature that makes it safe to work around the computer. Oil boils at 175 C. If you have a few boiling racks you will not want humans in your server room and you'll probably burn down your air cooled servers. Oil cooled system will not used the clever technique used by Cray: no pump or other circulatory system was needed and working temperature was ultra stable. Fluorinert and oil cooling are completely different things and I don't think you can compare them.

To answer your question - the last Submersion cooled cray was the mid-90's era T90, which submersed 32 processor boards and the memory, in a pool of flourinert. It did not, howerver, submerse the rest of the system, in particular the I/O, which would use standard pin connectors. One of the more exotic pieces of technology in the T90 was the robotic claw connectors that clamped down on the edges of compute boards at 400 contacts per inch. The unit costs of these connectors were very high, in part because the

The only problem is that oil is a good solvent. Of course, computer equipment is obsolete in 3-5yrs, so maybe it's not an issue. However, the article mentions they tried motor oil first, so I wonder how much they actually thought this through. Motor oil, among other things, is much more viscous than traditional dielectric fluids. The fluids used in transformers are more like water in terms of viscosity. Lower viscosity provides better heat transfer. Also, since high dielectric strength is not an issue

This sounds good until the first oil cooled computer gets slashdotted. Then the fire department has to be called. At least the computer admins will be drenched in foam forcing them to shower more out of schedule.:)

Didn't IBM use oil-cooling on one of their mini/mainframe computer systems back in the day? I seem to recall hearing stories of low oil indicators on the machines. Unfortunately my Google searches on the subject are coming up dry...

Why does it have to be the entire rack? Wouldn't it be easier to just use oil in a liquid radiator system and deliver the fluid to the hot spots? Sure would make it simpler to get to the computers when something fails.

How this will reduce power usage? The same amount of heat is going to be generated by the computer equipment, it's going to get transferred out by the oil much better than traditional air cooling, but then the oil will still be transferring the heat to the server room. It's not like the oil is making energy disappear, it's just holding on to more of it and moving it away from the computer faster. The heat will still eventually be moved to the air in the server room, which will still need to be cooled to

no, not wondering if a hot swap involves one of those deep fryer baskets.But with comments about doing hardware swaps and waiting for oil drainage, can't these problems be solved with keeping some components in boxes/trays, and cirulating the oil in and out of each compartment via something similar to the dry break connectors used in some motorsport hoses.

That way you just yank it out and the only bit of oil to worry about is the amount immediately around the swapped part - which you could leave to drain, r

Except that the cost for A/C at datacenters (especially during the summer but even in winter, unless you have an outside air recirculator, which I imagine most datacenters do) is generally higher that the cost of running the computers. This is seriously no joke.I run a cybercafe with twenty machines. During the winter my electricity bill is cut by over 60% even though I have the same level of computer use. It's only because I don't need A/C. I almost never use a heater during the winter either. I actually h

I did not say cooling as 2-5% of operating cost. I said cooling is 2-5% of computer power. That means the fans or pumps only.

As you point out, total system cooling can be significant when AC is involved. But this will NOT change with oil-cooling. 98% of the heat will still be generated and have to be removed by the same AC units unless someone mounts external radiators.